1         () [] -> .                           left to right
     2         ! ~ ++ -- + - (type) * & sizeof      right to left
     3         * / %                                left to right
     4         + -                                  left to right
     5         << >>                                left to right
     6         < <= > >=                            left to right
     7         == !=                                left to right
     8         &                                    left to right
     9         ^                                    left to right
    10         |                                    left to right
    11         &&                                   left to right
    12         ||                                   left to right
    13         ?:                                   right to left
    14         = += -= *= /= %= <<= >>= &= ^= |=    right to left
    15         ,                                    left to right